Li et al

REVIEW ARTICLES Intoeinggaitinchildren

YHLi,JCYLeong

Objective. To review the aetiology and management of intoeing. Data sources. Medline and non-Medline literature search, and personal experience. Study selection. Studies that provided evidence-based information about the aetiology and management of paediatric intoeing gait were selected. Data extraction. Data were extracted and reviewed independently by both authors. Data synthesis. An intoeing gait affects many children and, as with flexible flatfoot, bowleg, and knock-knee, it falls into the category of physiological problems that occur in normal children. The usual causes are excessive femoral anteversion, internal tibial torsion, and metatarsus adductus. Management is based on understanding the causes and the natural course of the condition and the effectiveness of various treatment modalities. Unfortunately, due to a poor understanding of the condition, intoeing is commonly overtreated with braces or special footwear. Conclusions. Intoeing is one of the most common conditions encountered in paediatric orthopaedic practice. It is important to make an early diagnosis of pathological causes of intoeing such as cerebral palsy and develop- mental dysplasia of the hips so that treatment can be commenced as soon as possible.

HKMJ 1999;5:360-6

Key words: Child; Foot deformities, congenital; Gait; Hip joint/physiology; Movement

Terminology demonstrate torsion. Tibial version or torsion is the angle measured between the transmalleolar axis and Rotation refers to the twist of the femur or the tibia the bicondylar axis of the proximal tibia at the knee. about the long axis of each bone. Rotation that is nor- mal in direction and magnitude is defined as ‘version’ The embryology of lower-extremity version and that which is abnormal is termed ‘torsion’. Further- more, ‘normal’ is defined as plus or minus two standard A basic knowledge of the embryological and foetal deviations from the mean.1 development of the musculoskeletal system is import- ant in the understanding of lower-extremity version. Rotation of a bone is determined by the angle The lower-extremity limb buds first appear as paddle- between reference axes at the proximal and distal ends shaped buds during the fifth to sixth weeks of gesta- of each bone. Rotation of the femur, for instance, is tion. The early limb bud continues its formation by the angle between the axis of the head/neck and the the migration and proliferation of the differentiating axis of the distal condyles at the most posterior points. mesenchymal tissues. By the end of the sixth week, If the angle between the proximal and distal axes is the limb buds have flattened and formed terminal hand positive, the femur is ‘anteverted’. If the angle between and foot plates and the early external form of the the proximal and the distal axes is negative, the femur limb. At approximately 7 weeks, the longitudinal axes is ‘retroverted’. If the angle is greater than two stand- of the upper and lower limb buds are parallel. The ard deviations from the mean, then the femur will pre-axial components face dorsally and the post-axial borders face ventrally. In this period, the position of Duchess of Kent Children’s Hospital, 12 Sandy Bay Road, Sandy the limb buds relative to the trunk change in a pre- Bay, Hong Kong YH Li, FRCS (Edin), FHKAM (Orthopaedic Surgery) determined manner not related to muscle activity or Department of Orthopaedic Surgery, The University of Hong Kong, inherent osseous torsion. The upper limb buds rotate Queen Mary Hospital, Pokfulam, Hong Kong externally and the lower buds internally, bringing JCY Leong, FRCS (Edin), FHKAM (Orthopaedic Surgery) the great toe to the midline from its initial post- Correspondence to: Dr YH Li axial position. Afterwards, mechanical intrauterine

360 HKMJ Vol 5 No 4 December 1999 Intoeing gait in children moulding of the lower limbs of the foetus takes the child’s present problem or fear that the current place, causing the femurs to rotate externally and the problem will persist and cause some long-term tibiae to do so internally.2-4 disability such as arthritis7,8 or make it difficult for the child to participate in sports or function normally? Femoral anteversion at birth is about 30 to 40°. Enquire about any family history of rotational prob- Because of the common intrauterine position of hip lems. Take a developmental history and ask about external rotation, the infant appears on examination to the nature of the disability such as tripping or falling. have more hip external rotation than internal rotation. Find out if the child prefers to sit on the floor in the This soft tissue external hip rotation contracture ‘W’ or reversed tailor position. decreases over the first year of life and the increased hip internal rotation expected from the femoral The physical examination anteversion starts to become apparent. There is a When evaluating a patient with a rotational abnormal- gradual decrease in femoral anteversion from 30 to 40° ity, begin by assessing the rotational profile. This at birth to the value of 10 to 15° by early adolescence, allows one to measure the severity of the rotational with most of this improvement occurring before 8 years problem. The rotational profile provides the informa- of age.5 tion needed to establish a diagnosis and to quantify the severity of the rotational problem present. In a computed tomography (CT) study of tibial torsion in the growing fetus, it was found that there Firstly, inspect the patient standing from the front. was an increase in external tibial torsion in the early When excessive femoral anteversion exists, the patel- stages of foetal life but that this gradually decreased lae face each other medially. Secondly, ask the child so that in the newborn, the tibial torsion was internal. to walk towards you and estimate the foot-progression After birth, the tibia rotates externally and the average angle (FPA)—the angular difference between the long version of the tibia at skeletal maturity is 15°.6 axis of the foot and the line of progression. Intoeing is denoted by a minus sign and out-toeing by a plus Causes of an intoeing gait sign. In a normal child, the FPA is +10° with a range from -3 to +20°. Thirdly, examine the child prone with In the infant, the most common cause is metatarsus the knees flexed 90°. To determine the amount of hip adductus. With this condition, the entire forefoot is rotation, allow both hips to fall into maximum inter- adducted at the tarsometatarsal level but the hindfoot nal and external rotation. The legs should be allowed is in its normal position. When present in the second to fall by gravity alone—do not use force. The amount year of life, intoeing is commonly due to internal of internal and external rotation of the hip should tibial torsion. After 3 years of age, this problem is normally be similar and the total arc should be about usually due to excessive femoral anteversion. When a 90°. Medial rotation more than 70° suggests a diagno- child toes-in severely, a combination of causes should sis of excessive femoral anteversion. It is considered be suspected. mild if the degree of internal rotation is 70 to 80° and the external rotation is 10 to 20°; moderate if internal Sometimes a rotational problem is a manifestation rotation is 80 to 90° and lateral rotation is 0 to 10°; of an underlying disorder such as cerebral palsy and and severe if the internal rotation of the hip is greater hip dysplasia. Before focusing on the rotational than 90° with no external rotation (Fig 1). problem, a physician must check that the rest of the musculoskeletal system is normal. Any clinical find- To determine the degree of tibial rotation, the thigh- ings such as abnormal muscle tone, gait abnormality, foot angle or the transmalleolar angle needs to be limitation of hip abduction, and leg length discrepancy estimated. The thigh-foot angle is the angular differ- should prompt a more intensive evaluation. ence between the axis of the foot and the axis of the thigh when the patient is in the prone position with Performing an evaluation the knees flexed 90° and the foot and ankle in neutral position. A negative value is given when the tibia is Taking a history rotated internally (internal tibial torsion) and a posi- Intoeing is extremely common in infants and children tive value given when the tibia is rotated externally and is a frequent cause of anxiety in parents. It is (external tibial torsion). In the infant, the thigh-foot important to identify the reason for the consultation angle is internal (negative) but it becomes progressively and what the parents’ concerns are; the parents’ external (positive) with increasing age. During child- concerns must be taken seriously. In addition, is it hood, the mean thigh-foot angle is +10° with a range

HKMJ Vol 5 No 4 December 1999 361 Li et al

1a.

1b.

Fig 2. A negative thigh-foot angle in a patient with internal tibial torsion The normal angle is about +10 to +15°. In this patient, the angle is -20°

Imaging techniques used A physical examination usually provides sufficient information to formulate a treatment plan and further imaging is usually not required. There are, however, a number of imaging methods that can assess the amount of torsional deformity present in the bone. Imaging may need to be used in patients with hip dysplasia or cerebral palsy, or when significant Fig 1. Hip rotation in the prone position in a patient with excessive femoral anteversion rotational deformity does not resolve and corrective Normally, the internal and external rotation angles are more or surgery is needed. less the same (40-50°). In this patient, there is (1a) an increase in internal rotation to 70° and (1b) a decrease in external rotation to 20° Plain X-ray On an anteroposterior pelvis X-ray, an apparent coxa of -5 to +30° (Fig 2). If the foot is deformed, the valgus is shown due to femoral anteversion. To meas- thigh-foot angle cannot be used. Instead, the trans- ure the femoral anteversion, many radiographic tech- malleolar axis-thigh angle is used. The transmalleolar niques have been reported but most require the use axis is a line across the sole of the foot connecting of special positioning techniques or conversion tables9 the centers of the medial and lateral malleoli. A right and so are not useful in clinical practice. The main angle to this line is compared with the axis of the purpose of taking a plain X-ray in these patients is to thigh to provide the angle. rule out hip dysplasia. Radiographs of the tibia are not helpful in assessing tibial torsion. Finally, the shape and direction of the sole of the foot should be determined. The deformity can be Fluoroscopy assessed by projecting the bisector line of the heel to Fluoroscopy can help to quantitate the degree of fem- the forefoot to quantitate forefoot adduction. In the oral anteversion. The hip is rotated under fluoroscopy normal foot, this line projects between the second until a true AP view of the hip is obtained. The amount and third toes. In metatarsus adductus or in clubfoot, of internal rotation of the leg in that position is the the line projects toward the lateral toes. femoral anteversion.10

362 HKMJ Vol 5 No 4 December 1999 Intoeing gait in children

When evaluating the foot, the flexibility must be assessed. The deformity can be classified depending on the flexibility on passive correction. The foot is considered normal if the heel bisector line passes between the second and third toes. The deformity is classified as mild, moderate, or severe if the bisector passes through the third toe, the third and fourth web space, or the fourth and fifth web space, respectively.15

Most children who have metatarsus adductus at birth do not require treatment. If the child has a mod- erate or severe deformity that is not passively correct- able, casting or manipulation and taping is needed. It is prudent to wait until the child is older than 6 months before beginning casting or manipulation and taping because many feet correct spontaneously. Surgical treatment is only needed in the few cases of rigid and severe deformity that do not respond to conservative treatment. The usual indications are re- sidual metatarsus adductus in a child older than 3 to 4 years. Extensive tarsometatarsal capsulotomies16 are Fig 3. Computed tomography scan showing the done on the younger child, and multiple metatarsal femoral neck and the bicondylar axis of the distal osteotomies are performed on the older child. femur overlapping each other Excessive femoral anteversion is present and measures 56° (nor- mal adult value is approximately 15°) Internal tibial torsion

Computed tomography Children with internal tibial torsion walk with a pigeon- Computed tomography is the best imaging technique for toed or intoed gait. This is most common in children evaluating femoral anteversion. It should only be used, between the ages of 1 and 2 years. Involvement is however, when diagnosing a complex hip deformity or often bilateral; in unilateral cases, the left side is more when a rotational osteotomy is being contemplated. often involved. When the patellae are facing straight The angle formed by the bicondylar axis and a line up forward, the feet point inward. In the prone position, the femoral neck represents the amount of femoral the thigh-foot angle is negative. anteversion (Fig 3).11,12 Although CT scanning can be used to make a tibial rotation assessment, clinical The natural course of internal tibial torsion is evaluation is generally sufficient. spontaneous correction with growth.17 The affected child may trip and fall more easily but spontaneous Ultrasonography resolution is rapid in early childhood and there Ultrasonography can be used to measure the amount should be no residual disability. Clinical studies sug- of femoral or tibial torsion but this method is known gest that non-operative treatment of tibial torsion is to not be as accurate as using a CT scan.13,14 ineffective.18-20 Consequently, any treatment of tibial torsion in the infant or child is both unnecessary and Metatarsus adductus may even be harmful.

In a child with metatarsus adductus (sometimes Excessive femoral anteversion called metatarsus varus), the forefoot is adducted and the lateral border of the foot is convex. The medial Excessive femoral anteversion usually presents as a border is concave and a deep crease may be present. cause of intoeing at 3 to 4 years of age. It is present at Normally, a line bisecting the heel should traverse the birth but is masked by the lateral rotation contracture space between the second and third toes. In patients of the hip. Intoeing due to excessive femoral antever- with metatarsus adductus, the line will be directed sion increases up to 5 to 6 years of age and then grad- to the lateral toes. This deformity is differentiated ually decreases. It is more common in females, is from clubfoot in that the heel is not in an equinovarus familial, and is often symmetrical. When the child is position. standing, the patellae and knees are turned inward

HKMJ Vol 5 No 4 December 1999 363 Li et al the child prefers to sit in the ‘W’ or reversed tailor medial arch supports, can modify the pattern of shoe position. The FPA is negative and the child may trip wear but do not change the FPA. These minor shoe and fall easily because of crossing over of the feet. adjustments do not influence derotation of the femur When the patient is in the prone position, there is or tibia. excessive internal rotation of the hips (as much as 90°) and restriction of external rotation of the hips (0° in Intoeing causes secondary deformities of the severe cases). As the child gets older, compensatory spine, hip, and knee external rotation of the tibia may develop. This There is no evidence that intoeing can cause osteo- combination of excessive femoral anteversion and arthritis or back pain.7,8,21-23 Because runners often external tibial torsion will give rise to a torsional mal- demonstrate intoeing, some claim that a mild degree alignment syndrome causing an increase in the Q of intoeing may actually be beneficial. It is possible angle, patellofemoral joint instability, and anterior that mild intoeing facilitates running by placing the knee pain. toes in an optimal position to assist in ankle push-off.24

There has been speculation that excessive femoral Night splints can correct tibial and femoral anteversion may cause degenerative arthritis of the hip; torsional deformities however, it has recently been demonstrated that this is Night splints are not useful in remedying excessive not true.21-24 femoral anteversion. For internal tibial torsion, some clinicians claim success in using the Dennis-Brown Treatment of affected children splint but there has been no scientific proof of its usefulness. In the rabbit tibial model, lateral rotation The most important job of the physician is to establish forces have been shown to lead to angulation of the a correct diagnosis and to reassure the parents effect- cells within the zone of hypertrophy of the physis, but ively. The management of paediatric intoeing gait is no cortical remodelling occurs.25 In a similar rabbit illustrated in the flow chart (Fig 4). model, lateral rotation splinting changes the static foot angle but does not change bone rotation, which Common misconceptions indicates that the ‘correction’ achieved occurs primar- Shoes correct intoeing ily through the ankle joint, thus potentially damaging Shoe modifications, such as heel and sole wedges or the ankle joint.25

Intoeing

Screening examination to rule out hip dysplasia, cerebral palsy, etc

Rotational profile

>70° Internal rotation of the hip Negative thigh-foot angle Curved foot

Excessive femoral anteversion Internal tibial torsion Metatarsus adductus

Age 0-8 years Age >8 years Age 0-5 years Age >5 years flexible?

Observe Severe and Mild to Observe Severe and disabling Yes No disabling moderate

Age 0-8 months Age >8 months

Rotational Rotational Cast Cast osteotomy Observe osteotomy Observe correction correction

Fig 4. Management flow chart to be followed when treating a child with an intoeing gait

364 HKMJ Vol 5 No 4 December 1999 Intoeing gait in children

Non-surgical treatment staple fixation with a long leg plaster cast in place A careful evaluation of the child is essential and after for 6 to 8 weeks.27 Proximal intertrochanteric or sub- ruling out serious pathology, an effort must be made trochanteric osteotomy with blade-plate fixation is to establish what concerns the parents have. The advocated by some to avoid cast immobilisation in natural course of intoeing should be outlined and the older child and teenager (Fig 5).28 An alternative the common misconceptions surrounding intoeing is closed femoral derotation osteotomy and femoral explained. Reassurance should be given that the child intramedullary nailing, which allows the quickest will be followed up regularly and carefully. return to weight-bearing walking without the use of a cast.29 Intoeing due to excessive femoral anteversion and internal tibial torsion should not be treated with night Conclusion splints, twister cables, orthotics, or special shoes. These methods will not alter the natural course of these Intoeing is common in infants and children. The conditions. condition causes concern in parents and sometimes produces minor functional problems in children such Surgical treatment as frequent tripping. The parents’ concerns must be Derotation osteotomy is the surgical treatment of taken seriously. The child must be evaluated carefully choice for children with severe and persistent rotational and an accurate diagnosis made. Giving reassurance problems. An adequate number of years must pass to the parents is important. Most patients can be to make sure that the rotational deformities will not treated by observation alone and osteotomy is needed resolve naturally (Fig 4). Surgery should not be per- only rarely in the occasional patient with severe formed for a very young child. In general, tibial deformities that do not resolve with time. derotation osteotomy is seldom needed before age 5 years, and femoral derotation osteotomy should not References be done before 8 years. 1. Eckhoff DG, Winter WG. Symposium on femoral and tibial Patients with cerebral palsy more often have ex- torsion [editorial]. Clin Orthop Rel Res 1994;302:2-3. cessive femoral anteversion than do normal children 2. Guidera KJ, Ganey TM, Keneally CR, Ogden JA. The embry- and their anteversion seldom improves with time. It ology of low-extremity torsion. Clin Orthop Rel Res 1994;302: 17-21. may be appropriate to perform surgery in these pa- 3. Staheli LT. Torsional deformity. Pediatr Clin North Am tients at an earlier age. A tibial derotation osteotomy 1977;24:799-811. can be performed proximally or distally; however, there 4. Staheli LT, Corbett M, Wyss C, King H. Lower extremity are fewer complications with the distal osteotomy.26 rotational problems in children. Normal values to guide management. J Bone Joint Surg 1985;67A:39. 5. Fabry G, MacEwen GD, Shands AR Jr. Torsion of the femur: Femoral derotation osteotomy can be performed a follow-up study in normal and abnormal conditions. J Bone anywhere along the rotated femur. In children younger Joint Surg 1973;53A:1726-38. than 10 years, femoral osteotomy is most easily 6. Badelon O, Bensahel H, Folinais D, Lassale B. Tibiofibular achieved by a distal osteotomy stabilised by pin or torsion from the fetal period until birth. J Pediatr Orthop 1989; 9:169-73. 7. Eckhoff DG, Kramer RC, Alongi CA. Femoral anteversion and arthritis of the knee. J Pediatr Orthop 1994;14:608-10. 8. Terjesen T, Benum P, Anda S, Svenningsen S. Increased femoral anteversion and osteoarthritis of the hip joint. Acta Orthop Scand 1982;53:571-5. 9. Kane TJ, Henry G, Furry DL. A simple roentgenographic measurement of femoral anteversion. J Bone Joint Surg 1992;74A:1540-2. 10. Rogers SP. A method for determining the angle of torsion of the neck of the femur. J Bone Joint Surg 1931;13A: 821-4. 11. Weiner DS, Cook AJ, Hoyt WA Jr, Oravec CE. Computed tomography in the measurement of femoral anteversion. Orthopedics 1978;1:299-306. 12. Fabry G, Cheng LX, Molenaers G. Normal and abnormal Fig 5. Derotation osteotomy at proximal femur is fixed with a torsional development in children. Clin Orthop Rel Res 1994; dynamic hip screw in a patient with unresolved excessive femo- 302:22-6. ral anteversion 13. Phillips HO, Greene WB, Guilford W, et al. Measurement of

HKMJ Vol 5 No 4 December 1999 365 Li et al

femoral torsion: comparison of standard roentgenographic 8:540-2. techniques with ultrasound. J Pediatr Orthop 1985;5:546-9. 22. Kitaoka HB, Weiner DS, Cook AJ et al. Relationship between 14. Joseph B, Carver RA, Bell MJ, et al. Measurement of tibial femoral anteversion and osteoarthritis of the hip. J Pediatr torsion by ultrasound. J Pediatr Orthop, 1987;7:317-23. Orthop 1989;9:396-404. 15. Bleck EE. Metatarsus adductus: classification and relationship 23. Wedge JH, Munkacsi I, Loback D. Anteversion of the femur to outcomes of treatment. J Pediatr Orthop 1983;3:2-9. and idiopathic osteoarthrosis of the hip. J Bone Joint Surg 1989; 16. Heyman CH, Herndon CH, Strong JM. Mobilization of the 71A:1040-3. tarsometatarsal and intermetatarsal joints for the correction of 24. Fuchs R, Staheli LT. Sprinting and intoeing. J Pediatr Orthop resistant adduction of the fore gait of the foot in congenital 1966;16:489-91. clubfoot or congenital metatarsus varus. J Bone Joint Surg 25. Moreland MS. Morphological effects of torsion applied to 1958;40A:299-309. growing bone: an in-vivo study in rabbits. J Bone Joint Surg 17. Weseley MS, Barenfeld PA, Eisenstein AL. Thoughts on 1980;62B:230-7. in-toeing: twenty years’ experience with over 5000 cases and 26. Krengel WF, Staheli LT. Tibial rotational osteotomy for a review of the literature. Foot Ankle 1981;2:49-57. idiopathic torsion: a comparison of the proximal and distal 18. Barlow DW, Staheli LT. Effects of lateral rotation splinting osteotomy levels. Clin Orthop Rel Res 1992;283:285-9. on lower extremity bone growth: an in-vivo study in rabbits. 27. Hoffer MM, Peitetto C, Koffman M. Supracondylar derota- J Pediatr Orthop 1991;11:583-7. tional osteotomy of the femur for internal rotation of the 19. Heinrich SD, Sharps C. Lower extremity torsional deformi- thigh in the cerebral palsied child. J Bone Joint Surg 1981;63: ties in children: a prospective comparison of two treatment 389-93. modalities. Orthop Trans 1989;13:554-5. 28. Payne LZ, DeLuca PA. Intertrochanteric versus supracondy- 20. Knittel G, Staheli LT. The effectiveness of shoe modifications lar osteotomy for severe femoral anteversion. J Pediatr Orthop for intoeing. Orthop Clin North Am 1976;7:1019-25. 1994;14:39-44. 21. Hubbard DD, Staheli LT, Chew DE, Mosca VS. Medial 29. Winquist RA. Closed intramedullary osteotomies of the femoral Torsion and osteoarthritis. J Pediatr Orthop 1988; femur. Clin Orthop Rel Res 1986;212:155-64.

Oncology 2000— From Molecules to Management 17th Meeting of the International Academy of Tumour Marker Oncology 5th Annual Scientific Symposium of the Hong Kong Cancer Institute Joint organisers: International Academy of Tumour Marker Oncology (IATMO); The Chinese University of Hong Kong; The Hong Kong University of Science and Technology

23-24 March 2000 Royal Plaza Hotel, Kowloon, Hong Kong, China

Areas covered: EBV and Cancer, Genetics, Tumour Markers, Plasma DNA Diagnostics, New Approaches to Cancer Treatment, Cancer Prevention, Multimodality Treatment

Enquiries: Professor PJ Johnson Department of Clinical Oncology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong, China

Tel: (852) 2632 2144 • Fax: (852) 2649 7426 • E-mail: [email protected]

366 HKMJ Vol 5 No 4 December 1999